For the third time this season premier trainer Chris Waller came away from a Sydney metropolitan meeting with four winners.

But Waller rejected any thoughts it might be getting easier to do.

"It's bloody hard," Waller said.

Velrosso, backed in from $5 to $2.80 favouritism in the TAB Sprint (1200m), joined High On Believing, Arinosa and Stout Hearted as Waller winners at Rosehill on Saturday.

As usual, Velrosso gave his supporters some anxious moments when he rounded the turn in last place.

But also as usual, he saved his best for last and stormed home under apprentice Jason Collett to beat Aeronautical ($7.50) by a half neck.

"It is heart in your mouth stuff but he likes to be ridden cold and he needs to be," Waller said.

"We've had some good days this season and that's the result of good staff.

"The team does a great job."

Waller has broken away from the field as he chases his third premiership with 32 winners to Gai Waterhouse's 15.

Velrosso is among the nominations for the Group One Epsom Handicap (1600m) on October 6 but Waller said that would not be his target.

"I've decided he is a sprinter so there will be no Epsom for him.

"We'll just get him to win another Saturday race before we think about stepping up in class."

Velrosso's win gave Collett a double after he won aboard Arinosa.

New Zealand's premier apprentice for the 2011-12 season, Collett has joined the Waller team on a permanent basis after a successful stint last year.

Although meticulous in everything he does, Waller proved he was only human when he left a lead bag off Key West who finished sixth behind Velrosso.

The mistake was found in time and Waller was fined $500 which he copped on the chin for a first offence.